SPECIFICATION SCASE SIZES: 2.5" 3.5" 4" and6" CASE MATERIAL: Steel black case TUBE & MOVEMENT: Stainless steel SOCKET: Steel with nickel plated CONNECTIONS: 1/4"NPT dependent on model&size, bottom, back left&right side AVAILABLE RANGES: 30"HgVAC to 150 psi & 30"Hg VAC to 300psi with temperature scales WINDOW (LENS) MATERIAL: Plastic and glass lens as standard ACCURACY: ASME B40.1Grade B (3-2-3%) OPTIONS&ACCESSORIES: Custom dial, metric scale, DIN 2.5% accuracy, recalibrators, special connections and more.